chore: don't override the manifest file

[lostman]

Description

Closes #1350.

Instead of overriding the Manifest file, this PR adds --override-{start-block, end-block, identifier} CLI options to forc-index {build, deploy}, which allows us to achieve what we need for the QA script without touching the manifest file.

It also looks like forc index build unnecessarily writes the module path to the manifest:

    let relative_wasm = rel_artifact_path.as_path().display().to_string();

    manifest.set_module(Module::Wasm(relative_wasm));

I think forc-index shouldn't modify the user's source files.

Testing steps

CI tests should pass.

Changelog

• Remove the write method from the Manifest
• forc-index build no longer overwrites the manifest file.
• Add CLI flags to change the start and end blocks and the identifier of the indexer being deployed.
• Change the QA script to use the new CLI flags instead of overwriting the manifest file.